Pressure is growing in Washington for new sanctions to be placed on Russia in order to push Moscow to wind down the war in Ukraine.

The Republican leader of the U.S. Senate said on Monday the chamber could begin work this month on a bill imposing stiff sanctions on Russia - and secondary sanctions on countries that trade with Russia - over its war in Ukraine.

The president said he would know in about two weeks if Russian President Vladimir Putin is committed to ending its war in Ukraine.